Problem: Khan.scratchpad.disable(); For every level Emily completes in her favorite game, she earns $510$ points. Emily already has $310$ points in the game and wants to end up with at least $2250$ points before she goes to bed. What is the minimum number of complete levels that Emily needs to complete to reach her goal?
Solution: To solve this, let's set up an expression to show how many points Emily will have after each level. Number of points $=$ $ $ Levels completed $\times$ Points per level $+$ Starting points Since Emily wants to have at least $2250$ points before going to bed, we can set up an inequality. Number of points $\geq 2250$ Levels completed $\times$ Points per level $+$ Starting points $\geq 2250$ We are solving for the number of levels to be completed, so let the number of levels be represented by the variable $x$ We can now plug in: $x \cdot 510 + 310 \geq 2250$ $ x \cdot 510 \geq 2250 - 310 $ $ x \cdot 510 \geq 1940 $ $x \geq \dfrac{1940}{510} \approx 3.80$ Since Emily won't get points unless she completes the entire level, we round $3.80$ up to $4$ Emily must complete at least 4 levels.